The fuel dispensing nozzle having a dripless spout relates to nozzles used to dispense gasoline into automobile fuel tanks in general and more specifically to improvements in the spout, the gland, the attitude support device, and the air bleed device to reduce the drops of fuel after fueling. A unique aspect of the present dripless spout is a texture applied to the interior surface of the spout and a hole in the attitude support device.
Well known in the art and the public, gasoline-dispensing nozzles of the type used in most service stations have a spout which is inserted into the inlet of the filler pipe of an automobile fuel tank. The diameter of the spout is less than that of the filler pipe resulting in a gap between the side of the spout and the filler pipe. Consequently, gasoline vapors escaped into the atmosphere. Escaped gasoline vapors raised pollution concerns and triggered government regulation of fuel dispensing nozzles. Regulations require such nozzles to reduce the pollutants released to the atmosphere. A flexible bellows assembly fitted over the spout meets the regulations. This is known as the balanced pressure nozzle. However, the regulations further address drops of fuel that exit the spout after fueling. A user releases a lever to stop fuel flow into the nozzle. Some fuel remains within the nozzle and the spout. Under gravity, the fuel exits the spout as drops and evaporates. The California Air Resources Board limits nozzles to no more than three drops emitted from a spout after fueling.
Prior art designs provided valves at the end of the spout to block drops. Though stopping the fuel drops, valves added to the weight and cost of a nozzle. Valves tended to corrode and to malfunction after substantial usage.
The present art overcomes the limitations of the prior art. That is, the art of the present invention, a dripless spout, retains fuel drops within the spout without a valve.
The difficulty in providing a dripless spout is shown by the operation of a typical nozzle. A user completes fueling and releases a lever on a nozzle. The nozzle retains fuel in the spout and internal parts of the nozzle that has not dispensed into an automobile's fuel tank. As the user replaces the nozzle at the pump, fuel follows gravity towards the distal end of the spout. The fuel encounters a valve that closes automatically upon release of the lever. Fuel forms drops beyond the valve at the distal end of the spout. As the valve wears, more fuel escapes and forms drops. The present invention overcomes these difficulties.
The use of nozzles to dispense fuel is known in the prior art. For example, the U.S. Pat. No. 5,127,451 to Fink and Mitchell discloses a fuel dispensing nozzle improvement of a bellows to trap fuel vapors during filling of a tank. The bellows surrounds the spout for its full length and captures vapors. However, upon nozzle shutoff, fuel remains in the spout by capillary attraction or otherwise. The undisclosed surface of the spout permits fuel to exit the spout as drops. Thus, the prior art type of devices do not provide for reducing the number of fuel drops leaving a nozzle.